阅读说明：本技术 一种碳化硅精细陶瓷用碳化硅微粉及其制备方法 (Silicon carbide micro powder for silicon carbide fine ceramic and preparation method thereof ) 是由 刘骏 蔡璐 刘波 王钢 汪国雄 张海波 于 2020-05-14 设计创作，主要内容包括：本发明公开了一种碳化硅精细陶瓷用碳化硅微粉及其制备方法,其原料组成按重量份比包括：水溶性酚醛树脂10-20份、正硅酸乙酯6-10份、对甲苯磺酰氯0.6-0.8份、酸溶液6-8份、碱溶液3-5份和催化剂0.1-0.3份,本发明涉及碳化硅微粉制备技术领域。该碳化硅精细陶瓷用碳化硅微粉及其制备方法,通过水溶性酚醛树脂和正硅酸乙酯进行混合,对混合溶液利用离心搅拌机进行搅拌,搅拌速率为800r/min,搅拌时间为30分钟,在溶液进行搅拌的同时向混合溶液中加入催化剂盐酸溶液,采用该工艺进行碳化硅微粉的制备,制备出来的碳化硅微粉不仅纯度高,而且碳化硅微粉在进行碳化硅浆料制备的时候固相含量也较高,碳化硅微粉所使用质量较高,生产出来的陶瓷质量更好。(The invention discloses a silicon carbide micro powder for silicon carbide fine ceramics and a preparation method thereof, wherein the silicon carbide micro powder comprises the following raw materials in parts by weight: the invention relates to the technical field of silicon carbide micro powder preparation, and discloses a silicon carbide micro powder preparation method, which comprises the following steps of 10-20 parts of water-soluble phenolic resin, 6-10 parts of ethyl orthosilicate, 0.6-0.8 part of paratoluensulfonyl chloride, 6-8 parts of an acid solution, 3-5 parts of an alkali solution and 0.1-0.3 part of a catalyst. According to the silicon carbide micro powder for the silicon carbide fine ceramic and the preparation method thereof, water-soluble phenolic resin and ethyl orthosilicate are mixed, the mixed solution is stirred by a centrifugal stirrer, the stirring speed is 800r/min, the stirring time is 30 minutes, a catalyst hydrochloric acid solution is added into the mixed solution while the solution is stirred, the silicon carbide micro powder is prepared by adopting the process, the prepared silicon carbide micro powder is high in purity, the solid phase content of the silicon carbide micro powder is higher when silicon carbide slurry is prepared, the using quality of the silicon carbide micro powder is higher, and the quality of the produced ceramic is better.)

1. The silicon carbide micro powder for the silicon carbide fine ceramic is characterized in that: the raw materials of the material comprise the following components in parts by weight: 10-20 parts of water-soluble phenolic resin, 6-10 parts of ethyl orthosilicate, 0.6-0.8 part of paratoluensulfonyl chloride, 6-8 parts of acid solution, 3-5 parts of alkali solution and 0.1-0.3 part of catalyst.

2. The silicon carbide fine powder for silicon carbide fine ceramics according to claim 1, characterized in that: the raw materials of the material comprise the following components in parts by weight: 10 parts of water-soluble phenolic resin, 6 parts of ethyl orthosilicate, 0.6 part of paratoluensulfonyl chloride, 6 parts of acid solution, 3 parts of alkali solution and 0.1 part of catalyst.

3. The silicon carbide fine powder for silicon carbide fine ceramics according to claim 1, characterized in that: the raw materials of the material comprise the following components in parts by weight: 20 parts of water-soluble phenolic resin, 10 parts of ethyl orthosilicate, 0.8 part of paratoluensulfonyl chloride, 8 parts of acid solution, 5 parts of alkali solution and 0.3 part of catalyst.

4. The silicon carbide fine powder for silicon carbide fine ceramics according to claim 1, characterized in that: the raw materials of the material comprise the following components in parts by weight: 15 parts of water-soluble phenolic resin, 8 parts of ethyl orthosilicate, 0.7 part of paratoluensulfonyl chloride, 7 parts of acid solution, 4 parts of alkali solution and 0.2 part of catalyst.

5. The fine silicon carbide powder for fine silicon carbide ceramics according to any one of claims 1 to 4, characterized in that: the catalyst adopts hydrochloric acid solution, and the concentration of the hydrochloric acid solution is 5.5%.

6. The fine silicon carbide powder for fine silicon carbide ceramics according to any one of claims 1 to 4, characterized in that: the acid solution is hydrofluoric acid solution, and the concentration of the hydrofluoric acid solution is 10%.

7. The fine silicon carbide powder for fine silicon carbide ceramics according to any one of claims 1 to 4, characterized in that: the alkali solution is sodium hydroxide solution, and the concentration of the sodium hydroxide solution is 35%.

8. A preparation method of silicon carbide micro powder for silicon carbide fine ceramics is characterized by comprising the following steps: the method specifically comprises the following steps:

s1, mixing the water-soluble phenolic resin and the ethyl orthosilicate, stirring the mixed solution by using a centrifugal stirrer at a stirring speed of 800r/min for 30 minutes, adding a catalyst hydrochloric acid solution into the mixed solution while stirring the solution, promoting the ethyl orthosilicate in the mixed solution to hydrolyze by using the hydrochloric acid solution, controlling the pH value of the mixed solution to be 4.5-6, and then adding p-toluenesulfonyl chloride into the stirred mixed solution, wherein the water-soluble phenolic resin: ethyl orthosilicate: catalyst: p-toluenesulfonyl chloride ═ 5: 1.5: 0.08: 0.1;

s2, sintering the mixed solution in the S1 in a sectional heating mode, wherein the first section temperature is 150 ℃, the sintering time is 10 minutes, the second section temperature is 300 ℃, the sintering time is 20 minutes, the third section temperature is 650 ℃, the sintering time is 15 minutes, and the fourth section temperature is 1300 ℃, so that silicon carbide crystals are generated;

s3, performing ball milling on the silicon carbide crystal obtained in the S2 by using a ball mill, wherein the ball milling time is 12 hours, performing acid washing on the silicon carbide crystal subjected to ball milling by using an acid solution for 3 times, then adding an alkali solution into the silicon carbide crystal for precipitation, adjusting the pH value of the solution to 9-11, uniformly stirring the precipitated material, conveying the material into a centrifuge for dehydration, and drying the silicon carbide powder by using a flash evaporation dryer after the dehydration is completed, wherein during drying, the air inlet temperature is controlled to be 180 ℃, the indoor temperature is controlled to be 100 ℃, the air outlet temperature is controlled to be 90 ℃, and finally, the silicon carbide crystal is subjected to cyclic grinding by using an ultrafine grinding stirring barrel until the particle size of the silicon carbide particles is 3mm, so that the silicon carbide micro powder is obtained.

Technical Field

The invention relates to the technical field of preparation of silicon carbide micro powder, in particular to silicon carbide micro powder for silicon carbide fine ceramics and a preparation method thereof.

Background

The silicon carbide ceramic not only has excellent normal-temperature mechanical properties such as high bending strength, excellent oxidation resistance, good corrosion resistance, high abrasion resistance and low friction coefficient, and the high-temperature mechanical properties (strength, creep resistance and the like) are the best among the known ceramic materials, and the materials are sintered by hot pressing, pressureless sintering and hot isostatic pressing, the high-temperature strength of the silicon carbide ceramic can be maintained to 1600 ℃, the silicon carbide ceramic is the best material in ceramic materials with the best high-temperature strength, the oxidation resistance is also the best material in all non-oxide ceramics, the silicon carbide ceramic is named as carborundum, the silicon carbide ceramic is a material with extremely high covalent bond, the hardness is high, the chemical corrosion resistance is good, the oxidation resistance is good, the thermal expansion coefficient is small, the thermal conductivity is high, the semiconductivity is good, the silicon carbide ceramic has a wide application range due to a plurality of excellent characteristics, and the silicon carbide ceramic has huge development potential in the aspects of high.

The carbon thermal reaction is one of the main methods for synthesizing silicon carbide powder, the main development direction of the carbon thermal synthesis of the silicon carbide powder is high in purity and controllable in particle size, the key is to select a proper silicon source, a proper carbon source and proper process conditions, the silicon source mostly adopts quartz sand, silicon dioxide powder, silicon powder, silane and the like, the selection of the carbon source is limited to graphite and carbon powder, the graphite and the carbon powder are used as the carbon source, the silicon carbide generated with the silicon powder and the like is mainly subjected to solid-phase reaction, the defects of limited contact area, insufficient reaction and the like exist in the solid-phase reaction process, the yield of the silicon carbide powder is influenced, and the purity of the obtained silicon carbide micro powder is low.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides silicon carbide micro powder for silicon carbide fine ceramics and a preparation method thereof, and solves the problems of low yield and purity of the silicon carbide micro powder prepared in the prior art and poor use quality of the silicon carbide micro powder.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: the silicon carbide micro powder for the silicon carbide fine ceramic comprises the following raw materials in parts by weight: 10-20 parts of water-soluble phenolic resin, 6-10 parts of ethyl orthosilicate, 0.6-0.8 part of paratoluensulfonyl chloride, 6-8 parts of acid solution, 3-5 parts of alkali solution and 0.1-0.3 part of catalyst.

Preferably, the raw materials comprise the following components in parts by weight: 10 parts of water-soluble phenolic resin, 6 parts of ethyl orthosilicate, 0.6 part of paratoluensulfonyl chloride, 6 parts of acid solution, 3 parts of alkali solution and 0.1 part of catalyst.

Preferably, the raw materials comprise the following components in parts by weight: 20 parts of water-soluble phenolic resin, 10 parts of ethyl orthosilicate, 0.8 part of paratoluensulfonyl chloride, 8 parts of acid solution, 5 parts of alkali solution and 0.3 part of catalyst.

Preferably, the raw materials comprise the following components in parts by weight: 15 parts of water-soluble phenolic resin, 8 parts of ethyl orthosilicate, 0.7 part of paratoluensulfonyl chloride, 7 parts of acid solution, 4 parts of alkali solution and 0.2 part of catalyst.

Preferably, the catalyst adopts hydrochloric acid solution, and the concentration of the hydrochloric acid solution is 5.5%.

Preferably, the acid solution is a hydrofluoric acid solution, and the concentration of the hydrofluoric acid solution is 10%.

Preferably, the alkali solution is sodium hydroxide solution, and the concentration of the sodium hydroxide solution is 35%.

The invention also discloses a preparation method of the silicon carbide micro powder for the silicon carbide fine ceramic, which comprises the following steps:

s1, mixing the water-soluble phenolic resin and the ethyl orthosilicate, stirring the mixed solution by using a centrifugal stirrer at a stirring speed of 800r/min for 30 minutes, adding a catalyst hydrochloric acid solution into the mixed solution while stirring the solution, promoting the ethyl orthosilicate in the mixed solution to hydrolyze by using the hydrochloric acid solution, controlling the pH value of the mixed solution to be 4.5-6, and then adding p-toluenesulfonyl chloride into the stirred mixed solution, wherein the water-soluble phenolic resin: ethyl orthosilicate: catalyst: p-toluenesulfonyl chloride ═ 5: 1.5: 0.08: 0.1;

s2, sintering the mixed solution in the S1 in a sectional heating mode, wherein the first section temperature is 150 ℃, the sintering time is 10 minutes, the second section temperature is 300 ℃, the sintering time is 20 minutes, the third section temperature is 650 ℃, the sintering time is 15 minutes, and the fourth section temperature is 1300 ℃, so that silicon carbide crystals are generated;

s3, performing ball milling on the silicon carbide crystal obtained in the S2 by using a ball mill, wherein the ball milling time is 12 hours, performing acid washing on the silicon carbide crystal subjected to ball milling by using an acid solution for 3 times, then adding an alkali solution into the silicon carbide crystal for precipitation, adjusting the pH value of the solution to 9-11, uniformly stirring the precipitated material, conveying the material into a centrifuge for dehydration, and drying the silicon carbide powder by using a flash evaporation dryer after the dehydration is completed, wherein during drying, the air inlet temperature is controlled to be 180 ℃, the indoor temperature is controlled to be 100 ℃, the air outlet temperature is controlled to be 90 ℃, and finally, the silicon carbide crystal is subjected to cyclic grinding by using an ultrafine grinding stirring barrel until the particle size of the silicon carbide particles is 3mm, so that the silicon carbide micro powder is obtained.

(III) advantageous effects

The invention provides silicon carbide micro powder for silicon carbide fine ceramics and a preparation method thereof. Compared with the prior art, the method has the following beneficial effects:

the preparation method of the silicon carbide micro powder for the silicon carbide fine ceramic comprises the steps of S1, taking water-soluble phenolic resin and ethyl orthosilicate for mixing, stirring the mixed solution by using a centrifugal stirrer, wherein the stirring speed is 800r/min, the stirring time is 30 minutes, adding a catalyst hydrochloric acid solution into the mixed solution while stirring the solution, promoting the ethyl orthosilicate in the mixed solution to hydrolyze by using the hydrochloric acid solution, controlling the pH value of the mixed solution to be 4.5-6, and then adding p-toluenesulfonyl chloride into the stirred mixed solution, wherein the water-soluble phenolic resin: ethyl orthosilicate: catalyst: p-toluenesulfonyl chloride ═ 5: 1.5: 0.08: 0.1; s2, sintering the mixed solution in the S1 in a sectional heating mode, wherein the first section temperature is 150 ℃, the sintering time is 10 minutes, the second section temperature is 300 ℃, the sintering time is 20 minutes, the third section temperature is 650 ℃, the sintering time is 15 minutes, and the fourth section temperature is 1300 ℃, so that silicon carbide crystals are generated; s3, performing ball milling on the silicon carbide crystal obtained in the S2 by using a ball mill, wherein the ball milling time is 12 hours, performing acid washing on the silicon carbide crystal subjected to ball milling by using an acid solution for 3 times, then adding an alkali solution into the silicon carbide crystal for precipitation, adjusting the pH value of the solution to 9-11, uniformly stirring the precipitated material, conveying the material into a centrifuge for dehydration, and drying the silicon carbide powder by using a flash evaporation dryer after the dehydration is completed, wherein during drying, the air inlet temperature is controlled to be 180 ℃, the indoor temperature is controlled to be 100 ℃, the air outlet temperature is controlled to be 90 ℃, finally, the silicon carbide crystal is circularly ground by using an ultrafine grinding stirring barrel until the particle size of the silicon carbide particle is 3mm, so that silicon carbide micro powder is obtained, the preparation of the silicon carbide micro powder is performed by adopting the process, the prepared silicon carbide micro powder has high yield and purity after detection, and the solid phase content of the silicon carbide slurry prepared by adopting the silicon carbide micro powder is higher, the used quality of the silicon carbide micro powder is higher, and the quality of the produced ceramic is better.

Drawings

FIG. 1 is a statistical table of comparative experimental data according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1, the embodiment of the present invention provides three technical solutions: a preparation method of silicon carbide micro powder for silicon carbide fine ceramics specifically comprises the following embodiments: